Green's Function Solutions of 1- and 2-D Dual-Phase-Lag Laser Heating Problems in Nano/Microstructures

2021 ◽  
Author(s):  
William Troy ◽  
Mitra Dutta ◽  
Michael Stroscio
Keyword(s):  
Laser Heating ◽  
Laser Cutting ◽  
Large Temperature ◽  
Phase Lag ◽  
Dual Phase ◽  
Biological Applications ◽  
Tumor Irradiation ◽  
Spatial Domains ◽  
Temporal And Spatial ◽  
Slow Propagation

Abstract Lasers and laser heating have a wide variety of applications such as spectroscopy, laser welding, laser cutting, and even biological applications like tumor irradiation and surgery. Theoretical modeling of laser heating has proven to be quite difficult, and classical heating equations have shown to be inaccurate due to the large temperature gradients created by the laser heating. Furthermore, the commonly-used Fourier's Law assumed the speed for a thermal wave to propagate as infinite; this is unrealistic in any medium and especially in domains with slow propagation speeds such as biological media and in fast nano/microscale heating applications. This study helps fill some of the gaps in accurate model of laser heating by presenting unique 1-D and 2-D models of the analytically solved Dual-Phase-Lag (DPL) heating equations which can much more accurately describe the temperature of such interactions in both the temporal and spatial domains.

Numerical Simulation of Heat Transfer Mechanisms During Femtosecond Laser Heating of Nano-Films Using 3-D Dual Phase Lag Model

Volume 4 ◽  
2004 ◽  
Author(s):  
Illayathambi Kunadian ◽  
J. M. McDonough ◽  
K. A. Tagavi
Keyword(s):  
Heat Conduction ◽  
Femtosecond Laser ◽  
Laser Heating ◽  
Three Dimensions ◽  
Grid Function ◽  
Hyperbolic Heat Conduction ◽  
Phase Lag ◽  
Dual Phase ◽  
Time Step ◽  
Eigenmode Analysis

In the present work we investigate femtosecond laser heating of nanoscale metal films irradiated by a pulsating laser in three dimensions using the Dual Phase Lag (DPL) model and consider laser heating at different locations on the metal film. A numerical solution based on an explicit finite-difference method has been employed to solve the DPL heat conduction equation. The stability criterion for selecting a time step size is obtained using von Neumann eigenmode analysis, and grid function convergence tests have been performed. The energy absorption rate, which is used to model femtosecond laser heating, has been modified to accommodate for the three-dimensional laser heating. We compare our results with classical diffusion and hyperbolic heat conduction models and demonstrate significant differences among these three approaches. The present research enables us to study ultrafast laser heating mechanisms of nano-films in 3D.

Thermal Stress Associated With Non-Fourier Heat Conduction in Femtosecond Laser Heating of Multilayer Metallic Films

2018 ◽  
Author(s):  
Swarup Bag ◽  
M. Ruhul Amin
Keyword(s):  
Thin Film ◽  
Heat Conduction ◽  
Thermal Stress ◽  
Temperature Distribution ◽  
Pulse Laser ◽  
Laser Heating ◽  
Laser Source ◽  
Phase Lag ◽  
Dual Phase ◽  
Fourier Heat Conduction

In the present work, the deformation behavior in metallic film subjected to ultra-short laser heating is investigated. Static thermo-elastic behavior is predicted for 100 nm thin film of either single layer or multiple layers. The temperature distribution is estimated from dual-phase lag non-Fourier heat conduction model. The maximum temperature after single pulse is achieved 730 K. The temperature profile for this pulse laser is used to compute elastic stress and distortion field following the minimization of potential energy of the system. In the present work, the simulation has been proposed by developing 3D finite element based coupled thermo-elastic model using dual phase lag effect. The experimental basis of transient temperature distribution in ultra-short pulse laser is extremely difficult or nearly impossible, the model results have been validated with literature reported thermal results. Since the temperature distribution due to pulse laser source varies with time, the stress analysis is performed in incremental mode. Hence, a sequentially coupled thermo-mechanical model is developed that is synchronized between thermal and mechanical analysis in each time steps of transient problem. The maximum equivalent stress is achieved 0.3 GPa. Numerical results show that the predicted thermal stress may exceeds the tensile strength of the material and may lead to crack or damage the thin film.

Analysis of dual-phase-lag heat conduction in short-pulse laser heating of metals with a hybrid method

2013 ◽  
Vol 52 (2) ◽  
pp. 275-283 ◽  
Author(s):  
Haw-Long Lee ◽  
Wen-Lih Chen ◽  
Win-Jin Chang ◽  
Eing-Jer Wei ◽  
Yu-Ching Yang
Keyword(s):  
Heat Conduction ◽  
Pulse Laser ◽  
Hybrid Method ◽  
Laser Heating ◽  
Short Pulse ◽  
Phase Lag ◽  
Dual Phase ◽  
Short Pulse Laser ◽  
Pulse Laser Heating

On the Analysis of Short-Pulse Laser Heating of Metals Using the Dual Phase Lag Heat Conduction Model

2009 ◽  
Vol 131 (11) ◽  
Author(s):  
K. Ramadan ◽  
W. R. Tyfour ◽  
M. A. Al-Nimr
Keyword(s):  
Heat Flux ◽  
Heat Conduction ◽  
Laser Heating ◽  
Flux Distribution ◽  
Heat Losses ◽  
Phase Lag ◽  
Dual Phase ◽  
Heat Flux Distribution ◽  
Conduction Model ◽  
Initial Heat

Transient heat conduction in a thin metal film exposed to short-pulse laser heating is studied using the dual phase lag heat conduction model. The initial heat flux distribution in the film, resulting from the temporal distribution function of the laser pulse, together with the zero temperature gradients at the boundaries normally used in literature with the presumption that they are equivalent to negligible boundary heat losses is analyzed in detail in this paper. The analysis presented here shows that using zero temperature gradients at the boundaries within the framework of the dual phase lag heat conduction model does not guarantee negligible boundary heat losses unless the initial heat flux distribution is negligibly small. Depending on the value of the initial heat flux distribution, the presumed negligible heat losses from the boundaries can be even way larger than the heat flux at any location within the film during the picosecond laser heating process. Predictions of the reflectivity change of thin gold films due to a laser short heat pulse using the dual phase lag model with constant phase lags are found to deviate considerably from the experimental data. The dual phase lag model is found to overestimate the transient temperature in the thermalization stage of the laser heating process of metal films, although it is still superior to the parabolic and hyperbolic one-step models.

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